William b



Patented Apr. Z9, 1890. I

(No Model.)

W. B. MASON. DAMPER REGULATOR.

NITE STATES ArnNr rrrcng VILLIAM B. MASON, OF BOSTON, MASSACHUSETTS,ASSIGNOR TO THE MASON REGULATOR COMPANY, OF SAME PLACE.

DANI PER-REG U LATO R.

SPECIFICATION forming part of Letters Patent No. 426,885, dated April29, 1890.

Application filed October 4, 1889.

To all whom, it may concern:

Be it known vthat I, WILLIAM B. MASON, of Boston, county of Suffolk, andState of Massachusetts, have invented an Improvement inDamper-Regulators, of which the following description, in connectionwith the accompanying drawings, is a specification, like letters on thedrawings representing like parts.

My invention relates to a damper-regulator for controlling the operationof the furnace of a steam-generator in accordance with the pressure ofthe steam produced, thereby checking the fire as the pressure risesabove the desired limit and increasing the fire when the pressure fallsbelow the said limit, so that the pressure is automatically maintainedsubstantially constant, only a slight variation from the predeterminedpoint being required to cause the proper change in the condition of thefire to prevent further variation in the pressure of the steam.

The invention is shown embodied in a damper-regulator of that class inwhich a valve is made responsive to changes in pressure of the steam andcontrols the action of a motive fluid upon a motor or engine that opensand closes the damper or other draftregulating device to thereby governthe condition of the fire in the furnace.

While the apparatus is described as controlling the draft of thefurnace, it is obvious that it is equally applicable to any means forcontrolling the fire or heat by which the pressure that it is desired tomaintain constant is generated-as, for example, by controlling theadmission of the fuel in case a gaseous or liquid fuel is employed-andit is furthermore obvious that the apparatus is not necessarily used tocontrol steam-pressure, as the operation would be the same with otherfluids.

The invention consists, mainly, in details of construction of theregulating apparatus, by which it is made compact and at the same timepositive and reliable in operation and convenient for attachment to theboiler and furnace or other pressure-generator.

Figure l is a vertical longitudinal section of a damper-regulator deviceembodying this invention; Fig. 2, a detail to be referred to,- and Fig.3 a modification to be referred to.

The instrument comprises a motor consisting of a cylinder d and piston bmovable Serial No. 325,975. (No model.)

therein, said piston being connected preferably by a iieXible connectoror chain b2 with a pulley b3, fixed upon a shaft c, provided with apulley d, which may be connected with the damper, slide, or other devicethat directly controls the fire by which the pressure to be regulated isproduced. This connection is illustrated in Fig. l, in which a portionof the chimney or uptake is represented in small scale at e, the saidchimney containing a damper of usual construction, the shaft of which isprovided with an operating-arm e2, one end of which is provided with aweight es or otherwise acted upon with a tendency to open the damper,while the other end of said arm is connected by a cord or other flexibleconnector e4 with the pulley d, the end of said cord being fastened tothe periphery of the pulley, as indicated at d2, so that the rotation ofthe pulley produced by downward movement of the piston Z9 will turn thelever e2 ou its fulcrum, raising the weight e3 and closing the damper inthe chimney e. The shaft. c has its bearing in a chamber a2, formedabove the cylinder aand having its interior in communication with oneend of said cylinder, the pulley b3 and chain connector b2 beingcontained within the chamber d2, which may be made, as shown, in thesame casting with the cylinder ct.

Steam or other actuating fluid is admitted into the chamber 502,' so asto act upon the upper end of the piston b and force the same downward inthe cylinder d through the port f-,which connects the interior of thechamber a2 with a space or pressure-chamber g, communicating withtheboiler or other source of iiuid under pressure through an inlet-pipe h.The space g thus always contains the actuating-fluid under pressure, andthe passage of the said fluid through the port fto act on the pist-on bis controlled by a diaphragm 7c, which is itself acted upon by adefinite controllable force, shown in this instance as derived from aspring m, which tends to hold the diaphragm seated upon a a seat at theend of the port f, and thus to prevent the admission of theactuating-fluid through the port'f to the chamber d2 and cyliuder ct.

Vhen, as in the present instance, the motor is operated by the fluid thevariable pressure of which is intended to regulate or govern theoperation of the motor, the diaphragm which is exposed to the variablepressure of the fluid may, and in the present case does, itselfconstitute the valve that controls the adlnission of fluid to the motor,said diaphragm practically constituting one wall of the pressure-chamberg, so that when the pressure is suflieient to overcome the predeterminedforce of the spring it raises said diaphragm and thereby opens the portleading to t-he motor.

rl`l1e port may be, as shown, formed in a piece of pipe secured in themain casting of lthe motor and finished at its end to form a suitableseat for the diaphragm, this being a far simpler, less expensive, andmore efficient construction than when the diaphragm is employed to movea valve constituting a sepa rate device or part of the apparatus toccntrol the port, as has been heretofore practiced.

The spring m is regulated by afollowermg, adjustable by a screw m3, soas to exert a pressure on the diaphragm 7,'. suiiicientto balance thenormal pressure which it is desired to maintain in the fluid, andconsequently if the 'fluid-pressure is below the normal the spring mwill overbalance it and will retain the port f closed, preventing theadmission of fluid into the cylinder u., so that the piston l) and shaftc and pulley CZ connected therewith will be acted on only by the weighte3 (see Fig. l) and will move the said shaft in the direction to openthe damper or permit the heat to act with maximum effect in thesteamgenerator, thus tending to increase the iinidpressure. Then underthe action of the heat the fluid-pressure rises to the predeterminedamount, its pressure on the diaphragm 7s just balances that ofthe springm, and the slightest increase in pressure will raise the diaphragm andthus open the port fand admit the fluid to the cylinder u, which inacting upon the piston bwill move the same and the connected pulley (lin the direction to close the damper or otherwise check the applicationof heatto the generator, so that the pressure will not be furtherincreased, and when the pressure falls below the predetermined amountthe admission of fluid will again be cut off by the diaphragm t' andpermit the weight e to act and again open the damper to increase theheat.

In order to permit the return movement of the piston l) under the actionof the weight c, it is necessary to exhaust the fluid from the space inthe cylinder above the piston. This may be performed in any suitablemanner. As herein shown, the piston l) is provided with a leak-passage,as indicated at p, Fig. l, or otherwise made slightly leaky, so as topermit the fluid to pass through the piston into the space a3 in thecylinder a, below the piston, but more slowly than the fluid is admittedthrough the port f,so as not to materially diminish the pressure on thepiston l; when the port j' is open. When the port]I is closed,

however,so that the admission of fluid to the cylinder is cut off, theweight e3 in moving the piston back will cause the fluid to pass throughthe piston to the other side thereof, or into the exhaust-chamber a3,and said fluid acts asacushion to prevent t-oo sudden movement of thepiston when admission of the fluid is cutoff. At the next downwardmovement of the piston I) the fluid which was previously exhaustedthrough it into the space d3 will have to be disposed of, and for thispurpose the space a3 is provided with au exhaust-passage fr, which mayopen directly inte the atmosphere, as shown in Fig. l, or may convey theexhaust-fluid toany desired point.

The exhaust-passage ris shown as made in the end plate at of thecylinder.

XVith the parts thus far described the opening of the port f on theslight increase of pressure above the normal permits the :fluid to actcontinuously on the piston l), and thus cause the damper orheat-controller to wholly close until the pressure again falls to orslightly below the normal.

It is sometimes desirable to regulate the heat more closely inaccordance with the demands to be put upon it in keeping the pressure upto the normal, so that when the pressnre rises above the normal thedamper, instead of being' wholly closed, and thereby producing thegreatest possible check upon the fire, will be partially closed, andthus check the fire sufficiently to prevent further increase ofpressure, and thereby maintain the fire steady and uniform at about thecondition required to maintain the desired pressure instead oflmaintaining the same by frequently varying the fire from maximum tominimum intensity. In order to accomplish this result, in accordancewith this invention means are provided for slightly varying the pressureof the valve-controlling spring nl, as the damper is moved. In order toaccomplish this result the upper portion m" of the chamber that inclosesthe spring m is made movable IOO IIO

with relation to the lower portion of the said chamber, and theadjustable support on, for the follower m2, that sustains directly theupper end of the spring m, is connected with the said upper portion on"of the spring-chamber. Thus, while the upper portion of thespringchamber remains in fixed relation to the lower` y portion, thespring may be adjusted by its follower for any required fluid-pressureto be maintained; but after it is so adjusted a slight movement of theupper portion of the springchamber relative to the lower portion willproduce a eorrespondin g variation in the pressure of the spring on thediaphragm. To produce such variation in the pressure of the spring, theupper portion of the spring-chamber is acted upon by a cam or eccentricfm. see Fig. 2) on an arbor m, working' in a bracket m7 from the lowerportion of the spring-chamber, the said arbor m6 beingl provided with anarm m3, in proper position to be acted upon by a cam mi on the pulley d.

The operation of these parts may be best understood from Fig. 2, and isas follows: Vhen the piston b is in its highest positionthat is, withthe damper wide open, or so as to give the furnace its maximumheat-producing action-the arm m8 rests against the portion of the cam m9nearest the center of the pulley d, and the eccentric m5 is in posi- Clthe cam m throws the arm m8 outward, and

thus turns the eccentric/m5, so as to press the upper part m4 of thespring-chamber downward, thereby slightly increasing the pressure of thespring m on the diaphragm, which closes the port f and so preventsfurther movement of the piston b. If such partial closing of the damperis sufficient to check the fire so that no further increase in pressureis made, the parts will remain in this position; but if the consumptionof steam diminishes or the fire thus checked continues toincrease thepressure of the iiuid the port f will again be opened and a furthermovement of the piston h will ensue, causing further closing of thedamper and checking of the fire, and also again slightly increasing thepressure of the spring m, and thereby arresting such movement before thedamper is wholly closed. By this construction the damper will be causedto assume a position corresponding to the demand on the boiler forsteam, the position of the damper varying only slightly from time totime and practically maintaining a substantially uniform fire of suchamount as will maintain the normal pressure for the consumption of steamat any time.

It is a great advantage that the piston of the motor having a long`range of movement acts directly upon a rotated shaft connected4 with thedamper, as by this construction the damper-regulator may be placed inany convenient position with relation to the boiler and the suitable.connections easily made from it to the damper.

In the modification shown in Fig. 3 the connection between the piston band pulley-shaft cis made by a rack b2 and pinion Z930, and theinvention is not limited to the specific mechanical construction shown.

The chain-connection represented in Fig. l is generally more desirablethan the rack-connection shown in Fig. 3, as the latter requires aconside 'able space in the chamber a2 above the shaft, which space isnot needed in the construction shown in Fig. l.

Some of the features of construction of the herein-described contrivanceare applicable to other apparatus controlled by the variable pressure ofa fluid.

I claimW y l. The combination of a cylinder and piston therein andchamber surmounting and communicating with the cylinder, and a rotatin gshaft or arbor extending from the inside to the outside of said chamberand being operatively connected with said piston at the inside of saidchamber, with a diaphragm or piston acted upon at one side by apredetermined force and at the other side by a variable pressure of thefluid, the admission of which to said chamber and cylinder is controlledby said diaphragm, substantially as described.

2. The combination of the cylinder and piston movable therein andchamber surmounting a'nd communicating with the said cylinder, and therotating shaft extending from the inside to the outside of said chamberand being operatively connected with said piston, said chamber beingprovided with an inletport, and the said cylinder being provided with anexhaust-port, and there being a leak or connecting passage from one tothe other side of lsaid piston of less capacity than the inlet-port, anda diaphragm or piston acted upon at one side by a predetermined force,and at the other side by the variable pressure of a fluid, the admission'of which to said chamber is controlled by said diaphragm, substantiallyas and for the purpose described.

3. The combination, with the damper-motor,l of a valve controlling theadmission of motive fluid thereto, a spring acting on said valve, and amovable support for said spring, and connecting mechanism between saidmovable spring-support and the damper-motor, as described, whereby thepressure of the spring on the valve is increased in the movement of themotor that closes the damper, substantially as described.

4. The combination of a port or fluid-passage, as f, a pressure-chamberaround the same, the end of said passage constituting an annulusprojecting into the said chamber, and a diaphragm exposed to thepressure of the iiuid in said chamber and having a iiat portion integralor rigidly connected therewith,

,co-operating with the annular mouth of 'the said port, and constitutinga valve controlling the admission of fluid from said pressurechamberinto said port, substantially as and for the purpose described.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

IVM. B. MASON.

IVitnesses:

J os. P. LivERMoRE, M. E. HILL.

